The density and sound velocity measurements were carried out on l-valine (2-amino-3-methyl butanoic acid) in pure water and in aqueous solutions of 0.02 w/w of PEG400, PEG2000 and PEG6000 at T = (298.15, 308.15 and 318.15) K at ambient pressure. From these experimental data, the values of the apparent molar volume, isentropic compressibility and apparent molar isentropic compressibility were evaluated and fitted to the Redlich – Mayer equation from which the corresponding infinite dilution molar properties were obtained. Furthermore, the effect of molar mass PEG and temperature on the volumetric and comperssibility properties of the mentioned systems have been studied. The results show that the structure and molar mass of the polymer don't affect on the values of apparent molar volume, isentropic compressibility and apparent molar isentropic compressibility.
